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1.
研究页岩气的开发利用对缓解我国的能源危机,降低能源对外依存度具有重要意义。文章集中分析了页岩气勘探开发的重要性、我国近年来页岩气勘探开发的现状及政策,指出:开发利用页岩气主要存在未经证实的资源储备风险、开发技术方面的风险、自然环境风险、企业资金风险。分析认为,页岩气勘探开发需建立长期科学可行、可持续的规划;在环境风险管理监督方面、体制方面还需进一步完善。  相似文献   

2.
塔克拉玛干沙漠石油开发和国外合作的前景塔里木石油勘探开发指挥部刘欣和八十年代,我国与国外进行了广泛紧密的合作。依靠现代科学技术,对曾有“死亡之海”恶名、环境条件十分恶劣的塔克拉玛干沙漠进行了大规模的地貌、地质等综合性考察和勘探,掌握了大量丰富的资料,...  相似文献   

3.
"海绵城市"建设是我国应对城市雨水问题的新举措,目的是改善城市水文环境,促进城市雨水资源的可持续利用。国外尤其是发达国家已进行了多年的雨水利用理论研究与实践。对相关研究成果进行梳理并加以借鉴,将有助于促进我国"海绵城市"建设。通过文献分析法检索了世界知名出版社和数据库的相关论文,对国外近年来雨水资源利用的主要研究成果进行了总结和分类。结果表明,国外的雨水资源利用在雨水采集系统、技术应用、风险评价、社会学研究、低影响开发与最佳管理实践等领域取得了丰富的成果,在研究深度、广度和尺度上对我国的相关研究具有启发性。我国的"海绵城市"研究应吸收国外的优秀成果并与中国的城市特点相结合,全方位、系统性地开展研究和实践,为全国范围内的推广应用提供科学依据。  相似文献   

4.
生态风险评价是污泥环境风险评价的重要组成部分。本文通过对美国污泥土地利用生态风险评价的研究,阐述了污泥土地利用生态风险评价过程中涉及的基本概念和定量研究方法,并对存在的困难进行了探讨。文章建议我国应借鉴国外污泥土地利用生态风险评价的研究方法,尽快建立适合我国污泥处置的生态风险评价标准方法和指南,以发挥其在环境保护和管理中的作用。  相似文献   

5.
国外保护矿业环境的矿业立法择优   总被引:1,自引:0,他引:1  
勘探尤其是开采对环境的污染和破坏是比较典型的,为此,世界绝大多数国家制订了独立于矿产资源法的《矿业法》,从立法资源上保证保护矿业环境法律构建。国外《矿业法》以行政特许权授予为主要方式,综合运用了矿业主体、市场力量、公众参与其他方式保护矿业环境。源头控制、全过程控制、无过错和合力等原则是国外矿业法的立法原则。国外矿业法择优显得我国取代《矿业法》的《矿产资源法》关于矿业环境保护的规定过分“苛刻”。  相似文献   

6.
苗红娟  陈瑛 《资源开发与保护》2012,(1):66-67,79,F0003
世界铁矿资源分布不均匀,导致世界各国对铁矿资源的争夺非常激烈。在资源所在国直接投资是获取铁矿资源的主要方式之一,而投资区位选择又直接关系到铁矿企业与企业所在国对外直接投资的成败。分析了我国铁矿企业对外直接投资现状,指出了其存在的问题,探讨了铁矿资源丰富国家的投资环境,对我国铁矿企业对外直接投资风险的影响,并对我国铁矿企业的对外投资区位选择提出了建议。  相似文献   

7.
促进循环经济发展的税收对策   总被引:2,自引:0,他引:2  
循环经济是一种全新的经济模式,它关注的是资源减量、循环及再利用的问题。通过对国外为实现循环型经济所采取的税收政策的比较,分析我国目前在该领域采取的措施和存在的问题。并根据我国的实际情况,提出了促进发展循环经济的税收对策。  相似文献   

8.
我国风险投资起步于1985年,在一些技术和知识相对密集的高科技园区,成立了一批具有风险投资公司性质的创业中心,通过提供信息、管理、资金、市场等服务,促进了高新技术成果的商品化、产业化,发挥了“孵化器”的作用。目前,我国风险投资业尚存在如下一些问题:资本来源渠道狭窄,未能多元化,致使风险资本不足、规模小,不能有效支持高技术成果的产业化;由于缺乏风险投资管理人才、风险投资体制不健全等原因,使本不充裕的资金大量投向非风险领域。借鉴国外发展风险投资业的成功经验,我国必须加快立法,对已办的风险投资机构进行…  相似文献   

9.
为促进循环经济发展,加快建设资源节约型、环境友好型社会,国家发展和改革委员会于2006年12月24日发布了《“十一五”资源综合利用指导意见》(以下简称《指导意见》)。《指导意见》在分析我国资源综合利用现状的基础上,提出了2010年资源综合利用目标、重点领域、重点工程和保障措施。这是我国“十一五”期间资源综合利用工作的指导性文件,也是引导投资及决策重大项目的依据。全文如下。[编者按]  相似文献   

10.
页岩气勘探开发过程中的环境影响   总被引:3,自引:3,他引:0  
当前,我国正积极推进页岩气资源的勘探和开发工作,但其对环境的影响尚缺乏科学评价和规范管理。在系统分析页岩气勘探开发主要流程:井场选址与建设、水平井钻井、水力压裂和投产等的基础上,辨识了其造成生态破坏和环境污染的主要因素以及可借鉴的技术和经验。结合我国页岩气资源的分布和勘探开发现状,从法规政策、企业责任以及技术创新三个层面,提出我国页岩气开发过程中环境保护和管理应努力的方向。  相似文献   

11.
Fire and logging in nutrient-poor temperate forests with certain ericaceous understory plants may convert the forests into heaths. The process of disturbance-induced heath formation is documented by using examples ofCalluna in western Europe,Kalmia in Newfoundland, andGaultheria (salal) in coastal British Columbia. In a cool, temperate climate, rapid vegetative growth ofCalluna, Kalmia, and salal following disturbance results in increasing organic accumulation (paludification), nutrient sequestration, soil acidification, and allelochemicals. These are thought to be the main reasons to conifer regeneration failure in disturbed habitats. If continuation in forest is a land-use objective, then temperate forests with an ericaceous understory should not be logged unless effective silvicultural methods are devised to control the ericaceous plants and restore forest regeneration. Preharvest vegetation control may be considered as an option. Failure to control the understory plants may lead to a long-term vegetation shift, from forest to heathland, particularly in nutrient-poor sites. Successful methods of controllingKalmia andGaultheria, however, have yet to be developed. While theKalmia- andGaultheria- dominated heathlands are undesirable in Canada and the Pacific Northwest, a wide range ofCalluna heathlands of western Europe are being conserved as natural and seminatural vegetation.  相似文献   

12.
ABSTRACT: Sustained interest in and concern about the health status of the aquatic environment has resulted in extensive research focused on (1) effects of pollution on survival, growth, and reproduction of resource species at all life stages; (2) diseases of fish and shellfish, as they may be related to pollution and as they may serve as indicators of environmental stress; and (3) contaminant body burdens in fish and shellfish - their effects on the aquatic animals and their potential effects on humans. Effects, lethal and sublethal, of pollutants on life history stages of fish and shellfish have been documented, as have impacts on local stocks in badly degraded habitats, but as yet there has been no adequate quantitative demonstration of effects on entire aquatic species - probably because of the difficulty in sorting out relative effects of the many environmental factors that influence abundance. Sublethal effects, especially those that result in disease, have been examined intensively, and some diseases and disease syndromes have been associated statistically with pollution. Other pollution indicators (biochemical, physiological, genetic, behavioral, and ecological) have also received some attention, as have body burdens of contaminants in aquatic species. Research, especially that conducted during the past decade, has done much to clarify the many pathways and toxic effects of contaminants on aquatic animals, and has also helped to identify mechanisms for survival of fish and shellfish in the presence of environmental changes caused by human activities.  相似文献   

13.
In water stressed regions, water managers are exploring new horizons that would help in long‐range streamflow forecasts. Oceanic‐atmospheric oscillations have been shown to influence streamflow variability. In this study, long‐lead time streamflow forecasts are made using a multiclass kernel‐based data‐driven support vector machine (SVM) model. The extended streamflow records based on tree ring reconstructions were used to provide a longer time series data. Reconstructed data were used from 1658 to 1952 and the instrumental record was used from 1953 to 2007. Reconstructions for oceanic‐atmospheric oscillations included the El Niño‐Southern Oscillation, Pacific Decadal Oscillation, Atlantic Multidecadal Oscillation, and North Atlantic Oscillation. Streamflow forecasts using all four oscillations were made with one‐year to five‐year lead times for 21 gages in the western United States. This is the first study that uses both instrumental and reconstructed data of oscillations in SVM model to improve streamflow forecast lead time. SVM model was able to provide “satisfactory” to “very good” forecasts with one‐ to five‐year lead time for the selected gages. The use of all the oscillation indices helped in achieving better predictability compared to using individual oscillations. The SVM modeling results are better when compared with multiple linear regression model forecasts. The findings are statistical in nature and are expected to be useful for long‐term water resources planning and management.  相似文献   

14.
Urban ecological systems: scientific foundations and a decade of progress   总被引:9,自引:0,他引:9  
Urban ecological studies, including focus on cities, suburbs, and exurbs, while having deep roots in the early to mid 20th century, have burgeoned in the last several decades. We use the state factor approach to highlight the role of important aspects of climate, substrate, organisms, relief, and time in differentiating urban from non-urban areas, and for determining heterogeneity within spatially extensive metropolitan areas. In addition to reviewing key findings relevant to each state factor, we note the emergence of tentative "urban syndromes" concerning soils, streams, wildlife and plants, and homogenization of certain ecosystem functions, such as soil organic carbon dynamics. We note the utility of the ecosystem approach, the human ecosystem framework, and watersheds as integrative tools to tie information about multiple state factors together. The organismal component of urban complexes includes the social organization of the human population, and we review key modes by which human populations within urban areas are differentiated, and how such differentiation affects environmentally relevant actions. Emerging syntheses in land change science and ecological urban design are also summarized. The multifaceted frameworks and the growing urban knowledge base do however identify some pressing research needs.  相似文献   

15.
Urban gardens are important sources of sustenance for communities with limited access to food. Hence, this study focuses on food production in gardens in the Toledo metropolitan area in Northwest Ohio. We administered surveys to 150 garden managers from November 2014 to February 2015 in our attempt to better understand how neighbourhood racial composition and poverty levels are related to staffing and voluntarism, food production and distribution, the development of infrastructure, and the adoption of sustainability practices in urban gardens. The results from 30 gardens are presented in this paper. We used Geographic Information Systems to map the gardens and overlay the map with 2010 census data so that we could conduct demographic analyses of the neighbourhoods in which the gardens were located. Though the gardens were small – two acres or less – up to 46 varieties of food were grown in a single garden. Gardens also operated on small budgets. Food from the gardens was gifted or shared with friends, family, and neighbourhood residents. Gardens in predominantly minority neighbourhoods tended to have fewer institutional partners, less garden infrastructure, and had adopted fewer sustainable practices than gardens in predominantly White neighbourhoods. Nonetheless, residents of predominantly minority and high-poverty neighbourhoods participated in garden activities and influenced garden operations. Volunteering and staffing were racialised and gendered.  相似文献   

16.
All major journalism ethical codes explicitly state that journalists should protect editorial copy from undue influence by outside sources. However, much of the previous research on agricultural information has concentrated on what information various media communicate (gatekeeping studies) or communication's role in increasing innovation adoption (diffusion studies). Few studies have concentrated specifically on organizational and structural constraints that might adversely affect agricultural journalists' ethical standards; those that have, focus largely on farm magazines. A study of newspaper reporters who cover agricultural news found that the most pressing ethical concern is the effect of advertiser (agri-business) pressure on editorial copy, and that their concerns in general parallel those of farm magazine writers and editors. The majority reported being in situations in which they might be exposed to advertiser pressure, including pressures to change or withhold editorial copy. Large minorities suggested that advertising pressures affect the overall environment in which agricultural journalists work, and more than one in ten said they allow advertiser pressures to influence editorial decisions. The newspaper reporters who cover agricultural beats showed slightly more resistance to advertiser pressure than did farm magazine editors in a parallel study.  相似文献   

17.
Mapped environmental classifications are defined using various procedures, but there has been little evaluation of the differences in their ability to discriminate variation in independent ecological characteristics. We tested the performance of environmental classifications of the streams and rivers of France that had been defined from the same environmental data using geographic regionalization and numerical classification of individual river valley segments. Test data comprised invertebrate assemblages, water chemistry, and hydrological indexes obtained from sites throughout France. Classification performance was measured by analysis of similarity (ANOSIM). Geometric regions defined by a regular grid and without regard to environmental variables and a posteriori classifications based on clustering the test datasets defined lower and upper bounds of performance for a given number of classes. Differences in classification performances were generally small. The ANOSIM statistics for the a posteriori classifications were around twice that of all environmental classifications, including geometrically defined regions. The hydro-ecoregions performed slightly better for the invertebrate data and the network classification performed slightly better for the chemistry and hydrological data. Our results indicate that environmental classifications that are defined using different procedures can be comparable in terms of their ability to discriminate variation of ecological characteristics and that alleged differences in performance arising from different classification procedures can be small relative to unexplained variation. We conclude that definition procedures might have little effect on the performance of large-scale environmental classifications and decisions over which procedures to use should be based primarily on pragmatic considerations.  相似文献   

18.
Collisions with deer and other large animals are increasing, and the resulting economic costs and risks to public safety have made mitigation measures a priority for both city and wildlife managers. We created landscape models to describe and predict deer-vehicle collision (DVCs) within the City of Edmonton, Alberta. Models based on roadside characteristics revealed that DVCs occurred frequently where roadside vegetation was both denser and more diverse, and that DVCs were more likely to occur when the groomed width of roadside right-of-ways was smaller. No DVCs occurred where the width of the vegetation-free or manicured roadside buffer was greater than 40 m. Landscape-based models showed that DVCs were more likely in more heterogeneous landscapes where road densities were lower and speed limits were higher, and where non-forested vegetation such as farmland was in closer proximity to larger tracts of forest. These models can help wildlife and transportation managers to identify locations of high collision frequency for mitigation. Modifying certain landscape and roadside habitats can be an effective way to reduce deer-vehicle collisions.  相似文献   

19.
Manganese entering impounded water will undergo a cyclic transformation. Oxidation precipitates manganese from top waters. At the bottom of the lake, biological activity will render manganese soluble by both intracellular as well as extracellular activity. The study was made to demonstrate that biological reduction and transformation, organometallic complexation, together with the presence of carbon dioxide and the lowering of pH all have some effect on the solubility of manganese. Dissolved manganese may be brought back to top waters during the lake overturn and therefore deteriorates the water quality.  相似文献   

20.
Biodegradation of [A‐ring 14C] Estrone (E1), 17β‐estradiol (E2), and 17α‐ethinylestradiol (EE2) to 14CO2 was investigated under light and dark conditions in microcosms containing epilithon or sediment collected from Boulder Creek, Colorado. Mineralization of the estrogen A‐ring was observed in all sediment treatments, but not epilithon treatments. No difference in net mineralization between light and dark treatments was observed for 14C‐E2. Net mineralization of 14C‐E1 and 14C‐EE2 was enhanced in light treatments. Extents of 14CO2 accumulation and rates of mineralization were significantly greater for E2 than E1 under dark conditions, but were comparable under light conditions. These results indicate substantial differences in the uptake and metabolism of E1 and E2 in the environment and suggest biorecalcitrance of E1 relative to E2 in light‐limited environments. The extent of 14CO2 accumulation and rate of mineralization for EE2 in dark treatments were less than half of that observed for E2 and generally lower than for E1, consistent with previous reports of EE2 biorecalcitrance. However, 14CO2 accumulation and rates of mineralization were comparable for EE2, E2, and E1 under light conditions. These results indicate photoactivation and/or phototransformation/photodegradation processes can substantially enhance heterotrophic biodegradation of estrogens in sunlit environments and may play an important role in estrogen transport and attenuation.  相似文献   

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